1. Field of the Invention
The invention relates to a spot welding system capable of allowing pressurizing force applied to an object that is pressed to be constant, a method, and a computer program.
2. Description of the Related Art
Pressurizing force, which is applied to an object to be pressed such as a workpiece to be welded from a movable electrode of a spot welding gun, changes at each attitude of the spot welding gun. In order to allow the pressurizing force changed as above to be constant, there have been known technologies of measuring a change in the pressurizing force due to the movable electrode at each attitude of the spot welding gun by using a pressure sensor and calibrating a pressurizing force command to a servomotor that drives the movable electrode based on the measured change in the pressurizing force (Japanese Laid-open Patent Publication No. 2004-195545 and Japanese Laid-open Patent Publication No. 2005-66654).
According to the aforementioned conventional technique, since the attitudes of the spot welding gun are changed a plurality of times and pressurizing force due to the movable electrode is measured by the pressure sensor at the respective attitudes, calibration work is complicated.